Device for driving a rotary basket,particularly for dishwashers



Aug. 12, 1969 L. ZANUSSI 3,460,550 I DEVICE FOR muvzuo A ROTARY BASKET, mancumnm FOR DISHWASHERS Filed Sept. 1. 1967 INVENTOR. L- 2mm, BY M ,M m

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3,460,550 DEVICE FOR DRIVING A ROTARY BASKET, PARTICULARLY FOR DISHWASHERS Lino Zanussi, Ronche di Fontanafredda, Italy, assignor to Industrie A. Zanussi S.p.A., Pordenone, Udme, Italy,

an Italian company Filed Sept. 1, 1967, Ser. No. 664,974 Claims priority, application Italy, Sept. 3, 1966,

. 20,217/ 66, Patent 776,633

Int. Cl. 1308b 3/06 US. Cl. 134-112 9 Claims ABSTRACT OF THE DISCLOSURE Driving device for the basket in dishwashers, wherein said basket is rotated by means of hydraulic pressure.

BACKGROUND OF THE INVENTION This invention relates to a driving device for a basket, particularly applicable to dishwashers and is intended to solve in a simple manner a few problems inherent in said applications without resorting to more or less complicated electrical and mechanical devices. Usually, in the rotary basket type of dishwashers the drive is transferred by means of a roller which adheres to an outer rim or another suitable surface formed on said basket. It should be noticed that said baskets, due to their particular constructional arrangement, are never perfectly circular and thus a certain oscillation of the driving roller is necessary during operation. Moreover, the rotary basket is nearly always removable and thus mounted on appropriate guideways.

It is thus necessary that the introduction of said basket be followed by a pressural action by the roller as the basket has taken its working position.

SUMMARY OF THE INVENTION All these requirements have been fulfilled by the present invention which consists in causing the driving roller to adhere to the basket by utilizing the hydraulic pressure which obtains in the washing circuit or in the feeding main of the dishwasher. By so doing, once the basket has been loaded and introduced, the roller is caused to adhere thereto by virtue of the hydraulic pressure.

The device of the present invention will be more particularly disclosed referring to an only illustrative and not limiting embodiment, with reference to the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 shows in particular the device of the invention,

FIG. 2 is a schematic view of a dishwasher including the device of FIG. 1;

FIG. 3 is a detailed view in enlarged scale of the device of FIG. 1 and FIG. 4 is a detailed view on an enlarged scale of a further embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the figures, a dishwasher cabinet, diagrammatically denoted at 1, comprises a pump 2, a sprinkler 3 of the type which is driven to rotation by reaction and carries a small sheave 4, with the latter transferring the drive, through a resilient belt 5, to a larger sheave 6 keyed to a mainshaft 7. The mainshaft 7 carries in its bottom end a knurled roller 8 (see also FIG. 3) which adheres to a ring 9 of a resilient material mounted on a rotary basket 10. The lower end of the mainshaft 7 is in the shape of a bush 11 into which a pin 12 is slipped, the latter is a part of a plunger 13. The plunger 13 is slid- United States Patent O" 3,460,550 Patented Aug. 12, 1969 able within a cylinder 14, and the cylinder communicates via a fitting 15 and piping 17 with delivery side 1-6 of the circulation pump 2.

The pump has a suction side 18 which opens into a washing chamber or compartment 19. The plunger 13 slides, with a certain clearance, with-in the cylinder 14 which is open at the side away from the fitting 15 since no absolute tightness is required as any possible liquid spillage can be collected in the washing chamber 19. A slight leakage could even be desirable so as to avoid any possible friction or jamming.

The top portion (see FIG. 2) of the mainshaft 7 is housed in a coupling 20, which holds a resilient ring 21 to retain a bushing 22 into which the end of the shaft 7 is slipped, so that the shaft can be easily rotated while being allowed slightly to swing in the direction of the arrows 23, with the oscillations being such as to allow for a certain play of the driving roller 8 so as to follow, undisturbed, the displacements of the plunger 13.

Having now thus described the details of the device, its operation is believed self-explanatory. In point of fact, as the pump 2 is started, the delivery side 16 becomes pressurized and the rotary sprinkler 3 rapidly rotates and transfers its rotary drive, properly reduced, from the sheave 4 to the sheave 6 immediately. Through the properly sized piping 17 and fitting 15, the pressure of the delivery side 16 acts, with a slight time lag, upon the plunger 13, and the latter causes the mainshaft 7 to be shifted in the direction of the arrow 24 (FIG. 3), so as to approach the driving roller 8 to the resilient ring 9, whereby rotations imparted to the basket 10.

In FIG. 4 there is disclosed a modification of the invention in which an elastically extensible body is employed in lieu of the plunger 13. More specifically, it will be seen that an elastically extensible body 113 is mounted or guided in a cylindrical casing 114 and a hydraulic connection 115 is provided for the interior of the body 113. The mainshaft 7, knurled roller 8, ring 9,. basket 10, bush 11 and pin 12 are similar to the elements illustrated in FIG. 3.

Both the disclosure and the drawings clearly illustrate the features of the instant device, which virtually utilizes the hydraulic pressure for causing the driving roller to approach the rotary basket of a dishwasher. The important advantages of the invention are:

The possibility of adjusting and varying the contact pressure of the driving roller,

The possibility of allowing for adequate oscillations due to the imperfect circular outline of the rotary basket, with the oscillations being accomplished by the upper suspension assembly (FIG. 2) of the mainshaft 7,

The possibility of delaying the contact of the roller with the basket, thus permitting the former to store a certain momentum before transferring its drive to the basket, and

The possibility of releasing the pressure on the roller so as to facilitate the withdrawal of the basket.

All that has been disclosed in the foregoing in connection with the utilization of the hydraulic pressure obtaining in the washing circuit can also be achieved by exploiting the hydraulic pressure of the feeding main.

What is claimed is:

1. In a dishwashing machine having a rotary basket and a drive for the basket, the drive comprising a driving rollers means adherent to the basket, means for exerting hydraulic pressure to obtain adherence of the roller means to the basket, and said hydraulic pressure on the roller means being exerted with a certain time lag with respect to the start of the rotary motion of the roller means.

2. The device according to claim 1, characterized in that said hydraulic pressure used to cause the driving roller means to adhere to the basket is taken from the washing circuit.

3. The device according to claim 2, characterized in that said driving rollers means is acted upon by a movable member subject to the hydraulic pressure exerted by a feeding pump of sprinkling members.

4. The device according to claim 3, characterized in that a throttling is provided in piping which connects the delivery side of the feeding pump with said movable member.

5. The device according to claim 3, characterized in that said driving roller means is mounted in the neighbourhood of a mainshaft, in correspondence with either end whereby said movable member is active, with the other end of said shaft being resiliently supported so as to permit limited oscillations.

6. The device according to claim 3, characterized in that said movable member consists of a plunger, slidable within a single-action cylinder.

7. The device according to claim 6, characterized in that said plunger is slidable with a clearance within its respective cylinder, with the cylinder being open at its side away of the side at which pressure is exerted.

8. The device as claimed in claim 3 in which said movable member is an elastically extensible body.

9. The device according to claim 1, characterized in that the hydraulic pressure used to cause the driving roller means to adhere to the basket is taken from the feeding main.

References Cited UNITED STATES PATENTS ROBERT L. BLEUTGE, Primary Examiner US. Cl. X.R. l34-14l, 153 

